Charge forming device for internal combustion engines



c. A. FRENCH 2,071,116

CHARGE FORMING DEVICE FOR INTERNAL COMBUSTION ENGINES Feb. 16, 1937.

Filed April 10, 1935 forming device particularly adapted to Patented Feb. 16, 1937 COIHBUSTION ENG Charles A. French, Riverside, Ill., assignor to International Harves tion of New Jersey Application April 10,

ter Company, a corporais'ss, Serial No. 15,540

5 Claims.- (c1. 123-119) This invention relates to a charge forming device for internal combustion engines. More specifically it relates to a vaporizing and charge utilize less volatile fuels, than'those ordinarily employed.

A principal object of the invention is to provide means for vaporization of a heavy fuel, means to separate the vapor from the liquid particles and to deliver the vapor to an engine manifold at a properly metered rate.

Another object is to provide a device in which hot exhaust gases from an engine may be utilized to vaporize a heavy'fuel and to superheat the vapor prior to its mixture with air for combustion.

Another object is to provide means for regulating the amount of exhaust gas, and, at the same time, the amount of heat supplied to a vaporizing device by controlling a variable restriction in the exhaust discharge conduit of the engine. I

Another-object is to incorporate in a charge forming device a pressure responsive means actuated by pressure in the inlet manifold to regulate the amount of heat supplied to a vaporizing device. These objects and others which will be apparent from the detailed description to follow are accomplished by an arrangement of elements as shown in the drawing, in which:

A single figure shows diagrammatically an engine with inlet and exhaust manifolds therefor and a vaporizing device associated with the manifolds.

In the conventional carburetors used on internal combustion engines to supply a combustible charge, the liquid must be carefully metered to obtain a satisfactory mixture over a wide range of load on the engine. In the use of so-called heavy fuels, that is,-fuels of a much lessjvolatile nature,it is very difficult to meter the liquid and to deliver it uniformly to the inlet ports of a multiple cylindergengine.

In 'applicants construction to-be hereinafter described many of the variables encountered in ordinary carburetion, such as'viscosity, inertia, small orifices, jets, and the like have been eliminated. In the drawing a constant level float-chamber In supplied with fuel by a conduit ll maintains a predetermined, uniform liquid level in the vaporizing chamber l3. Said chamber may be constructed in any suitable shape and is preferably insulated to prevent the transfer of'heattherefrom. A balance tube It is provided between the float chamber Ill and the vaporizing chamberl3 above the liquid level therein. A vaporizing gas inlet conduit l6 extends into the vaporizing chamber I3 and terminates below the normal liquid level therein. A cone-shaped member Il provided with a plurality of narrow openings II,

elbowsof the exhaust manifold 22. Inlet ports 23 1'0 .are shown in the dotted lines at the ends of an inlet manifold 24. Said ports are for the purpose of communicating with two adjacent cylinders, being of the type used in commercial four-cylinder engines. The inlet manifold 24 is formed 15 with the usual riser 25, in which a throttle valve 26 is positioned. At the inlet side of the throttle valve 26 the riser 25is formed with a venturi 21.

A vaporized gas, conduit 28 communicates with the throat of the venturi 21 for delivering there- 20 Y to combustible gas which forms with the air drawn into the inlet riser a combustible mixture. An exhaust gas conduit 29, usually termed an exhaust pipe, is connected to the exhaust manifold 22. The vaporized gas conduit 28 extends through the exhaust manifold 22 for the purpose of superheating the vaporized gas from the va-- porizer and communicates with the upper end of the vaporizer. The vaporizing gas conduit "'16 extends into the exhaust pipe 29, having an open end 30 facing opposite the direction of gas flow, whereby the' inertia of the flowing gas acts, in addition to pressure, to force gas through the vaporizing gas conduit IS. A throttle valve 3| is mounted in the exhaust pipe 29 at the discharge 35 side with respect to the inlet end 30 of the conduit l6;

A lever arm 32 connected to the shaft of the valve 3| is connected by a link 32' with a lever 33' fulcrumed on a bracket 29' secured to the pipe 29. The lever 33' is connected by a link 33 to a pressure responsive device consisting essentially of a casing 34 and an expansible bellows 35. The shaft 33 extends slldable through an opening in. the casing and is pivotally secured to a connecting "5 member 36 secured to the bellows. The other end of the bellows is secured in a gas-tight manner to one end of the casing.

A conduit'3l connected with the inlet manifold 24 trapsmlts the pressure therein to the interior of the bellows 35 through one end of the casing 3|.

In the operation of an engine equipped with the vaporizing and charge forming device above described a volatile liquid may be utilized for 5 starting the engine, or it may be put into operation until warmed up by other suitable means. After the engineis in operation, hot exhaust gases being delivered through the exhaust manifold 22 and the exhaust pipe 23 are drawn through a 1 the vaporizing conduit l6 and through liquid in the vaporizing chamber |3, forming a combustible gas at a rate proportional to the supply of sensible heat of the exhaust gases being delivered. The vaporized gases pass through the conduit 28 into the throat of the venturi 21, being mixed therein with air sufficient for proper engine operation. This combustible mixture .is delivered through the inlet manifold 24 to the engine, the supply being regulated by the throttle valve 26.

' Although the throttle valve 26 is the means by which the operator controls the supply of gases to the engine, an automatic control is incorporated in the system. The position of the valve 31 determines the pressure in the exhaust conduit and consequently affects the amount of exhaust gas delivered to the vaporizing chamber. It will be understood, therefore, that the amount of vaporizing gas passing through the vaporizing chamber and the amount of combustible gas formed therein is a result of the suction in the throat of the venturi 21 and the pressure in the exhaust conduit. In order to make this control automatic,

- the pressure responsive device is utilized. An inload.

crease in suction indicating closing of the throttle 26 in the inlet manifold 2i contracts the bellows 35 to move the throttle valve 3| to an open position, thereby reducing pressure in the exhaust conduit and decreasing the formation of combustible gas in the vaporizing chamber. When the throttle 26 is opened the valve 3| is closed thereby increasing the supply of combustible gas.

There is also another inherent controlling means in the device described, as the temperature of engine exhaust gas is proportional to the load on the engine. As the load on the engine increases, requiring as a result a richer and more plentiful supply of fuel, the sensible heat supplied to the vaporizer is increased, th'ereby increasing the gas vaporized and supplied to the inlet manifold.

By the methods of operation inherent in the vaporizer described and obtained by the controls incorporated therein, the charge forming system is to a large degree automatically acting to sup-" ply the required fuel to an engine over a substatitial range in its requirements due to variation in It is to be understood that applicant has shown and described only in a diagrammatic manner a charge forming system embodying a preferred form of his invention, but that he claims all modifications falling within thescope of the appended claims.

What is claimed is:

1. A charge forming device for internal combustion engines comprising, in combination with an inlet mixture conduit and an exhaust gas conduit, a vaporizing chamber, means for supplying liquid fuelthereto, means for delivering hot gases from the exhaust conduit to said chamber, means for delivering vaporized gases from said chamber to the inlet conduit; and means for regulating the vaporized gas supplied to the inlet conduit by means operated'by the suction in the inlet mixture conduit.

2. A charge forming device for-internal combustion engines comprising, in combination with an inlet mixture conduit and an exhaust gas conduit, a vaporizing chamber, means for supplying liquid fuel thereto, means for delivering hot gases from the exhaust conduit to said chamber, means for delivering vaporized gases from said chamber supply according the amount of vaporizing gas supplied to the- .vaporizing chamber.

to the inlet conduit, a throttle valve positioned in the inlet mixture conduit, and means for regulating the amount of vaporized gas supplied'to said conduit by suction operated means communicating therewith between the throttle valve and the inlet to the engine.

.3. A charge forming device for internal combustion engines comprising, in combination with an inlet ,mixture manifold and an exhaust gas manifold, a vaporizing chamber, .means for maintaining liquid fuel at a predetermined level in said chamber, means communicating with the exhaust manifold for delivering hot exhaust gases beneath the surface of. the liquid. in the vaporizing chamber, a throttle valve in the exhaust manifold at the discharge side of the communication with the vaporizing chamber, a

venturi formed in the intake to the inlet manifold, a vaporized gas conduit leading from the vaporizing chamber to the throat of said venturi, a throttle valve positioned between the venturi and the inlet to the engine, a pressure responsive device connected to the throttle valve in the exhaust conduit, and means for connecting said device with the inlet manifold at the engine side of the throttle valve whereby the pressure in the inlet manifold regulates the throttle inthe exhaust conduit thereby governing engine operation by back pressure on the exhaust conduit and regulating the rate of fuel supply by regulating the amount of vaporizing gas supplied to the vaporizing chamber.

4. A charge forming device for internal combustion engines comprising, in combination with an inlet mixture conduit provided with a throttle valve and an exhaustgas' conduit, a vaporizing chamber, means for maintaining liquid fuel therein, means for delivering hot gases from the exhaust conduit to said chamber, means for metering the rate of supply of said delivery according to engine load including a fluid pressure responsive means in communication with the inlet conduit on the engine inlet side vof the throttle valve, and means for delivering vaporized gases from the vaporizing chamber to the inlet conduit.

with the liquid in the vaporizing chamber, a throttle valve in the exhaust manifold at the discharge side of the communication with the vaporizing chamber, a vaporized gas conduit leading from the vaporizing chamber to the inlet manifold, a throttle valve positioned in the inlet manifold, a pressure responsive device connected to the throttle valve in the exhaust conduit, and fluid pressure transmitting means connecting said device with the inlet manifold at the engine side of the throttle valve whereby the pressure in the inlet manifold regulates the throttle tn the exhaust conduit thereby governing engine operation exhaust conduit and regulating the rate of fuel to engine load by regulating 'by back pressure on the the qexhaust manifold for delivering hot exhaust gases in contact 

